This invention relates to method and apparatus for installing conduit, particularly electrical conduit, in a confined space behind a wall in a building or dwelling.
In new buildings or dwellings, electrical conduits are usually placed in the wall framework before the wall panels are placed over the framework. Accordingly, the installation of conduits at this stage of construction poses no particular problem because the space is readily accessible. However, in completed dwellings in which the wall panels have been put into place, the installation of electrical conduit becomes a difficult task because the conduit must be routed into blind confined spaces. Where such walls have glass fibre insulation, or other filler, in them the task becomes especially difficult, if not impossible.
The present invention is directed to a new and improved method and apparatus for installing conduit in confined spaces behind walls which are already in place, and which can be used where insulation, or other filler, occupies the confined spaces in the framework behind the walls. With the present invention, conduit can be installed in such spaces with efficiency thereby promoting increased productivity in installing such conduit, and helping to avoid frustration during such procedures.
Briefly, according to the preferred embodiment of the present invention, a tape, commonly known as a "fish tape", is used in conjunction with a magnet. Access openings are provided to the confined space, and at one access opening one end of the fish tape is introduced into the confined space. This end of the fish tape contains a roller which is attracted by an electromagnet which is placed on the exterior of the wall. The electromagnet is mounted on a wheeled carriage. When the electromagnet is energized, it attracts the roller on the end of the tape, and when the carriage is moved toward another access opening, it rolls the roller along the interior of the wall to the other point of access. At the second point of access the conduit which is to be installed behind the wall is secured to the end of the fish tape containing the roller. Then the fish tape is withdrawn, thereby pulling the conduit through the confined space. Withdrawal of the tape, and hence pulling of the conduit through the confined space is accomplished by the means of a reel, or drum, on which the tape is wound, the drum being disposed on the exterior of the confined space near the first point of access.
The foregoing features, advantages, and benefits of the invention, along with additional ones, will be seen in the ensuing description and claims which should be considered in conjunction with the accompanying drawings. The drawings disclose a preferred embodiment of the invention according to the best mode contemplated at the present time in carrying out the invention.